1/2 inch in mm and decimal

1/2 in = 0.5 in = 12.700 mm. Closest metric drill: 12.7 mm.

Nearby drill sizes

Drill	Type	Inch	mm	Difference
7/16	fraction	.4375 in	11.112	-62.5 thou
29/64	fraction	.4531 in	11.509	-46.9 thou
15/32	fraction	.4688 in	11.906	-31.3 thou
31/64	fraction	.4844 in	12.303	-15.6 thou
1/2	fraction	.5000 in	12.700	0.0 thou
33/64	fraction	.5156 in	13.097	15.6 thou
17/32	fraction	.5313 in	13.494	31.3 thou
35/64	fraction	.5469 in	13.891	46.9 thou
9/16	fraction	.5625 in	14.287	62.5 thou

1 thou = 0.001 in = 0.0254 mm. Drills a few thou apart are usually interchangeable for clearance holes, but not for tap drills or reamer pilots.